1. Field of the Invention
The invention relates to bevel squares and in particular an improvement on the standard T-bevel square for use in measuring compound angles.
2. Description of the Related Art
T-bevel squares are well known in the art as a tool for measuring and verifying angles. This tool can be used to transfer an accurate angle measurement from a large-scale drawing directly to a project surface, or to take measurements and verify angles of a project surface. A T-bevel is composed basically of two pieces, the stock and the sliding adjustable blade. The sliding adjustable blade has a slot and is capable of movement relative to the stock by means of rotation on a bolt secured through the stock. A locknut or other similar locking device secures the adjustable blade in the desired position relative to the stock. U.S. Pat No. 1,691,801, a 1928 patent, discloses the standard T-bevel square with one of the most recent improvements in the art. This patent discloses a T-bevel in which the blade is pivotal and the shank is mounted within a grove located on the blade with a means provided to secure the shank in any desired position within the same plane as the blade.
However, there are some situations where it is necessary to determine compound angles in a single measurement. The typical roof valley construction is included among these cases. The T-bevel square is limited in the fact that it is only capable of measuring a single angle at a time as the adjustable blade is not capable of measuring angles in a plane that is not essentially parallel to the plane of the handle. This is not an effective means for determining angles when compound angle measurements are involved. However, there is nothing in the prior art which is capable of measuring or verifying compound angles.